_CP_dtx is equivalent to the result = dtx(expression) BASIC statement.
int _CP_dtx(CPSTR** result, double expression)
This function returns -1 if an error occurs. The error code is contained in _CP_errno.
/* Prints "F". */ CPSTR * s = _CP_str_null; _CP_dtx(&s,15.0); _CP_print(s);